Vacuum processing apparatus and a vacuum processing system

ABSTRACT

The vacuum processing apparatus has an atmospheric loader having a plurality of cassette tables and a transport unit for carrying wafers, a vacuum loader equipped with vacuum wafer-processing chambers and a vacuum transport chamber communicating with the processing chambers via gate valves, and a locking unit provided with a loading lock chamber and unloading lock chambers that have gate valves for connecting the atmospheric transport unit and vacuum transport chamber; wherein two etching chambers, formed by UHF-ECR reactors, are arranged symmetrically with respect to an axial line passing through the middle of the vacuum transport chamber and locking unit, only at the opposite side of the locking unit across the vacuum transport chamber, and at an acute angle with respect to the vacuum transport chamber, and UHF-ECR antennas, almost parallel to the foregoing axial line, are opened at the opposite side to that of the vacuum transport chamber.

This application is a Divisional application of application Ser. No.09/697,324, filed Oct. 27, 2000.

BACKGROUND OF THE INVENTION

The present invention relates to vacuum processing apparatuses, and,more particularly, to a vacuum processing apparatus suitable forproviding samples, namely, silicon substrates and the like, withsingle-wafer processing, such as etching, CVD (chemical vapordeposition), spattering, ashing, or rinsing, and to semiconductormanufacturing equipment using such a vacuum processing apparatus.

Vacuum processing apparatuses for processing samples can be broadlydivided into a cassette block type and a vacuum processing block type.The cassette block type has its front extending longitudinally withrespect to the bay passageway of semiconductor manufacturing equipmentand includes cassette-and-sample orientation alignment units andatmospheric robots; whereas, the vacuum processing block type has aloading lock chamber, an unloading lock chamber, vacuum processingchambers, vacuum post-processing chambers, vacuum pumps, vacuum robots,and the like.

According to the abovementioned equipment, for a corresponding vacuumprocessing apparatus, the samples within a cassette are each carriedfrom the cassette block to the loading lock chamber of the vacuumprocessing block by an atmospheric robot. The sample is furthertransferred from the loading lock chamber to a processing chamber by avacuum robot, and then, after being set on an electrode structure, thesample undergoes plasma etching or other similar processing. The sample,after being processed, is transported to and further processed in avacuum post-processing chamber, as required.

Examples of vacuum processing apparatuses for etching samples withplasma are disclosed in, for example, Patent Disclosure Collection1986—official Gazette Issue No. 8153, Patent Disclosure Collection1988—Official Gazette Issue No. 133532, Patent Disclosure Collection1994—Official Gazette Issue No. 30369, Patent Disclosure Collection1994—Official Gazette Issue No. 314729, Patent Disclosure Collection1994—Official Gazette Issue No. 314730, and U.S. Pat. Nos. 5,314,509 and5,784,799.

Vacuum processing apparatus based on the above-identified prior art hasa concentric or rectangular arrangement of processing chambers andloading/unloading lock chambers. For example, the apparatus set forth inU.S. Pat. No. 5,314,509 has a vacuum robot located near the center ofthe vacuum processing block, with three processing chambersconcentrically arranged around the robot and a loading lock chamber andan unloading lock chamber provided between the robot and the cassetteblock. Such apparatus has the problem that the transport arms of theatmospheric robot and vacuum robot have too wide a rotational anglerange, and, thus, that the entire apparatus requires a large floorspace.

At the same time, the processing chambers, vacuum pumps, and otherpiped/tubed units within the vacuum processing block of the vacuumprocessing apparatus require periodic and non-periodic maintenance, suchas checking and repairing. Accordingly, around the vacuum processingblock there are usually provided access doors to enable the maintenanceof the loading lock chamber, unloading lock chamber, processingchambers, vacuum robots, and various piped/tubed units.

Conventional vacuum processing apparatus can handle samples up to 8inches (about 200 mm) in diameter and not more than about 250 mm incassette width “Cw”. Even this cassette dimension, however, has theproblem that a large floor space is required. In addition, to allow forhandling larger samples, such as 12 inches (about 300 mm) in diameter“d”, since carrier pods are required, the cassette width “Cw” must beincreased to about 350 mm and the cassette block for storing multiplecarrier pods must also be increased in width. If the width of the vacuumprocessing block is to be determined according to such width of thecassette block, the entire vacuum processing apparatus will require alarger floor space. For example, in the case of a cassette block capableof accommodating four carrier pods, if the diameter “d” of the samplesis increased from the conventional 8 inches to 12 inches, cassettes willabsolutely need to be at least about 40 cm wide.

For general semiconductor manufacturing equipment, to ensure that alarge number of samples undergo various types of processing at the sametime, multiple sets of a vacuum processing apparatus which carry out thesame type of processing are located at one bay and samples are carriedbetween bays automatically or manually. Since such manufacturingequipment requires a high degree of cleanliness, the entire equipment isinstalled in a large cleanroom. Increases in the dimensions of a vacuumprocessing apparatus, associated with increases in sample diameter,result in an increased cleanroom-occupied floor area, which in turnleads to further increased construction costs for a cleanroom, which isalready high in construction costs. If multiple sets of a vacuumprocessing apparatus occupying a large floor area are to be installed incleanrooms of the same area, the number of vacuum processing apparatussets or the spacing between each set of the vacuum processing apparatusmust be reduced. Reduction in the number of vacuum processing apparatussets installed in cleanrooms of the same area will necessarily reducethe productivity of the semiconductor manufacturing equipment and thusincrease semiconductor manufacturing costs. Reduction in the spacingbetween each set of the vacuum processing apparatus results in shortageof the maintenance space required for check and repair services, therebydeteriorating the maintainability of the vacuum processing apparatussignificantly.

SUMMARY OF THE INVENTION

One object of the present invention is to provide a vacuum processingapparatus that can minimize its manufacturing costs while at the sametime providing flexibility to increases in sample diameter.

Another object of the present invention is to provide a vacuumprocessing apparatus which is excellent in maintainability and isflexible to increases in sample diameter.

Still another object of the present invention is to provide a vacuumprocessing apparatus, such as semiconductor manufacturing equipment,that can minimize its manufacturing costs while at the same time provideflexibility to increases in sample diameter and ensure a complement ofvacuum processing apparatuses, and which does not deterioratemaintainability.

The present invention is directed to a vacuum processing apparatushaving an atmospheric loader equipped with a plurality of cassettetables arranged close to each other, and with a transport unit forcarrying wafers from or to the cassette tables, a vacuum loader equippedwith vacuum wafer-processing chambers and with a vacuum transportchamber in communication with the processing chambers via gate valves,and a locking unit that includes loading and unloading lock chambersequipped with gate valves for connecting the foregoing atmospherictransport unit and vacuum transport chamber;

wherein two vacuum wafer-processing chambers, both formed by amagnetized UHF-band electromagnetic wave radiation/discharge reactor(hereinafter, referred to as the UHF-ECR reactor), have side wall innerunits and antennas so mounted as to permit disassembly, and they arearranged symmetrically with respect to an axial line passing through themiddle of the vacuum transport chamber and locking unit, only at theopposite side of the locking unit across the vacuum transport chamber,and in such a manner that the vacuum processing chambers form an acuteangle with respect to the vacuum transport chamber.

The present invention is directed to a vacuum processing apparatushaving an atmospheric loader equipped with a plurality of cassettetables arranged close to each other, and with a transport unit forcarrying wafers from or to the cassette tables, a vacuum loader equippedwith vacuum wafer-processing chambers and with a vacuum transportchamber in communication with the processing chambers via gate valves,and a locking unit that includes loading and unloading lock chambersequipped with gate valves for connecting the foregoing atmospherictransport unit and vacuum transport chamber;

wherein two vacuum wafer-processing chambers, both formed by the UHF-ECRreactor, are arranged symmetrically with respect to an axial linepassing through the middle of the vacuum transport chamber and lockingunit, only at the opposite side of the locking unit across the vacuumtransport chamber, and at an acute angle with respect to the vacuumtransport chamber, and the antennas of the UHF-ECR reactor are directedalmost in parallel to the aforementioned axial line and are opened atthe opposite side of the vacuum transport chamber.

The present invention is directed to a vacuum processing apparatushaving an atmospheric loader equipped with a plurality of cassettetables arranged close to each other, and with a transport unit forcarrying wafers from or to the cassette tables, a vacuum loader equippedwith vacuum wafer-processing chambers and with a vacuum transportchamber in communication with the processing chambers via gate valves,and a locking unit with loading and unloading lock chambers gate-valvedfor connecting the foregoing atmospheric transport unit and vacuumtransport chamber;

wherein two vacuum wafer-processing chambers, both formed by the UHF-ECRreactor, have side wall inner units and antennas so mounted as to permitdisassembly, and are arranged symmetrically with respect to an axialline passing through the middle of the vacuum transport chamber andlocking unit, only at the opposite side of the locking unit across thevacuum transport chamber, and at an acute angle with respect to thevacuum transport chamber, and the aforementioned atmospheric loader,vacuum loader, and locking unit are arranged into a T-shape.

The present invention is directed to a vacuum processing system havingmultiple sets of vacuum processing apparatuses arranged in parallel,each set of which further consists of an atmospheric loader equippedwith a plurality of cassette tables arranged close to each other, andwith a transport unit for carrying wafers from or to the cassettetables, a vacuum loader equipped with vacuum wafer-processing chambersand with a vacuum transport chamber in communication with the processingchambers via gate valves, and a locking unit that includes loading andunloading lock chambers equipped with gate valves for connecting theforegoing atmospheric transport unit and vacuum transport chamber;

wherein two vacuum wafer-processing chambers, both formed by the UHF-ECRreactor, are arranged symmetrically with respect to an axial linepassing through the middle of the vacuum transport chamber and lockingunit, only at the opposite side of the locking unit across the vacuumtransport chamber, and at an acute angle with respect to the vacuumtransport chamber, and the vacuum processing apparatus sets arranged inparallel have all their vacuum processing chambers arranged linearly.

According to the present invention, it is possible to minimize increasesin manufacturing costs, while at the same time providing flexibility toincreases in sample size, and to provide a vacuum processing apparatuswhich is excellent in maintainability. Also, incorporation of suchvacuum processing apparatus into semiconductor manufacturing equipmentmakes it possible to ensure the complement of vacuum processingapparatus and minimize manufacturing costs, while at the same timeproviding flexibility to increases in sample size, and to supplysemiconductor manufacturing equipment whose maintainability does notdeteriorate.

Furthermore, according to the present invention, one portion of thevacuum vessel constituting the processing chambers can be constructed asa section that can be opened and closed, and when this section directsthe processing chambers upward, components can be maintained in theirphysically stable status at the operator side in an almost horizontalposition by friction or by a securing section. Accordingly, since thetop of the processing chambers opens in the direction of the maintenancearea, maintenance personnel can easily both access the processingchambers and perform maintenance operations from the top. As a result,the maintenance personnel can easily handle components duringmaintenance, whereby maintainability is improved, which in turn enablesthe realization of a plasma processing apparatus which is excellent inmaintainability and the ease of operations and contributes to animprovement of the productivity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual diagram of an embodiment of a vacuum processingsystem according to the present invention.

FIG. 2 is a conceptual diagram showing the basic configuration of oneexample of a vacuum processing apparatus according to the presentinvention.

FIG. 3 is a schematic diagram of a side view of the apparatus shown inFIG. 2.

FIG. 4 is a diagram showing one maintenance mode of the apparatus shownin FIG. 2.

FIG. 5 is cutaway perspective view showing the maintenance status of oneplasma etching apparatus according to the present invention.

FIG. 6 is a cutaway perspective view showing the maintenance status ofanother plasma etching apparatus according to the present invention.

FIG. 7 is a cutaway perspective view showing the maintenance status ofstill another plasma etching apparatus embodied according to the presentinvention.

FIG. 8 is a diagram showing an embodiment of the present invention wherethe full-flat open-structured vacuum vessel is mounted in a plasmaprocessing system.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Embodiments of the present invention will be described hereunder withreference to the accompanying figures.

FIG. 1 shows a connected arrangement of three sets of vacuum processingapparatus 10, which represents one embodiment of the present invention.The three apparatus sets are shown as 10A, 10B, and 10C.

Prior to description of the vacuum processing system shown in FIG. 1, adescription will be given of the vacuum processing apparatus, based onFIGS. 2 to 4. FIG. 2 is a conceptual block diagram of the aforementionedembodiment of the vacuum processing apparatus according to the presentinvention, and FIG. 3 is a schematic diagram of this apparatus. Thevacuum processing apparatus shown in these figures, as one embodiment ofthe present invention, is a dry etching apparatus that uses gas plasmato etch the wafer to be processed. In the figures, vacuum processingapparatus 10 comprises atmospheric loader 1 equipped with a transportunit for carrying the wafers within cassettes 1 a, 1 b, and 1 c, from aplurality of mutually adjacent cassette tables 2 a, 2 b, and 2 c, or tocassette tables 2 a, 2 b, and 2 c; vacuum loader 7 equipped with vacuumwafer-processing chambers (etching chambers) 11 a and 11 b, and withvacuum transport chamber 16 which communicates with the processingchambers via gate valves 15 a and 15 b; and locking unit 6 that includesloading lock chamber 6 a and unloading lock chamber 6 b, both equippedwith a gate valve for connecting the atmospheric transport unit andvacuum transport chamber.

In this embodiment, cassette tables 2 a or 2 c are arranged in paralleland they always hold cassettes 1 a or 1 c in a position from which theycan be loaded/unloaded, more specifically, a fixed position on an almosthorizontal plane, without the original positions or directions of thecassette tables being disturbed. Cassette tables 2 a and 2 b arearranged next to one another in parallel. Cassette table 2 c is locatedat the rightmost end of tables 2 a and 2 b. Both cassettes 1 a and 1 bare used for accommodating unprocessed or processed wafers and have astorage capacity of multiple wafers (usually, 25 pieces). In this case,cassette 1 c is for accommodating the dummy wafers to undergo drycleaning with plasma (hereinafter, referred to as plasma cleaning) orfor collecting plasma-cleaned dummy wafers, and has a storage capacityof multiple wafers (usually, 25 pieces).

Loading lock chamber 6 a and unloading lock chamber 6 b that facecassette tables 2 a and 2 b, respectively, are arranged insideatmospheric loader 1, and transport unit 13 is located between cassettetables 2 a/2 b and lock chambers 6 a/6 b. Loading lock chamber 6 a hasvacuum exhaust unit 3 and gas induction unit 4 and can load unprocessedwafers into vacuum loader 7 via gate valve 12 a. Unloading lock chamber6 b, likewise, has vacuum exhaust unit 3 and gas induction unit 4, andcan take processed wafers out into atmospheric loader 1 via gate valve12 b. Transport unit 13 has a robot equipped with X-, Y-, Z- andtheta-axes, and operates to enable wafers 20 to be exchanged betweenlock chambers 6 a/6 b and cassettes 1 a/1 b and between lock chambers 6a/6 b and cassette 1 c.

Loading lock chamber 6 a and unloading lock chamber 6 b are connected tovacuum transport chamber 16 via gate valves 12 b and 12 c, respectively.In this case, vacuum transport chamber 16 is circular and etchingchambers 11 a and 11 b for vacuum processing are provided on both sidewalls of vacuum transport chamber 16 via gate valves 15 a and 15 b. Theetching chambers are described below as an example. Inside vacuumtransport chamber 16 there is provided a transport unit 14 that operatesto enable wafers 20 or dummy wafers 30 to be exchanged between loadinglock chamber 6 a, unloading lock chamber 6 b, and etching chambers 11 aand 11 b. Vacuum transport chamber 16 has also a vacuum exhaust unit 17which is capable of exhausting vacuum independently.

In this case, etching chambers 11 a and 11 b of the UHF-ECR reactor aresymmetrically arranged with the same configuration so as to enableetching. Etching chamber 11 a is described below as an example. Etchingchamber 11 a has a samples mount 8 a for placing wafers 20 and is alsoprovided with a discharge chamber so that discharge portion 7 a isformed above samples mount 8 a. Etching chamber 11 a has gas inductionunit 10 a for supplying a processing gas to discharge portion 7 a, andis also provided with vacuum exhaust unit 9 a for reducing the internalpressure of this etching chamber to the required level. In addition,etching chamber 11 a has a means for generating, in this case, UHF wavesand magnetic fields for converting into plasma the processing gas to besupplied to discharge portion 7 a.

In this case, the etching chamber contains sensor 18 that measuresplasma light emission intensity. The value that has been measured bysensor 18 is sent to control unit 19. Control unit 19 compares themeasured value with the required value and judges the time for cleaningthe inside of the etching chamber. Control unit 19 also controls vacuumtransport units 13 and 14, thus controlling the transfer of dummy wafers30 between cassette 1 c and etching chamber 11 a or 11 b.

In the vacuum processing apparatus thus configured, first, cassettes 1 aand 1 b containing unprocessed wafers are placed on cassette tables 2 aand 2 b, respectively, by a line transport robot that operates inaccordance with the information received from a host control unit, or bythe operator, whereas cassette 1 c containing dummy wafers is placed oncassette table 2 c. The processing apparatus conducts wafer processingor plasma cleaning, pursuant to either self-identification of theproduction information assigned to cassette 1 a or 1 c, the informationreceived from the host control unit, or the instruction entered by theoperator.

For example, vacuum transport units 13 and 14 carry wafers 20, in orderfrom bottom to top, from cassette 1 a to etching chambers 11 a and 11 b,where the wafers then undergo etching. After etching, wafers 20 arereturned to their original positions within cassette 1 a by vacuumtransport units 13 and 14. In this case, without changing the positionand direction of each wafer during the time from the start of operationto the end, the transport units take out unprocessed wafers and returnonly processed ones to the positions where they were stored before beingprocessed. Thus, application to automatic operation of semiconductormanufacturing equipment becomes easy and the contamination of waferswith dirt can be minimized and high production efficiency and highproduction yields can be achieved.

As etching progresses in the etching chamber 11 a or 11 b, reactionproducts stick to and accumulate on the inner wall of the etchingchamber. The reaction products must therefore be removed by plasmacleaning to restore the inside of the etching chamber to its originalstatus. The time to conduct plasma cleaning is judged by control unit19. In this case, since etching chamber 11 a or 11 b has a portion towhich plasma light penetrates, the luminous intensity of the plasmalight immediately after it has penetrated is measured by sensor 18 andwhen the measured luminous intensity reaches a required value, controlunit 19 judges that the time for plasma cleaning has been reached. Or,control unit 19 can be activated to count the number of wafers whichhave been processed in the etching chamber, and when the measuredluminous intensity reaches the required value, the time for plasmacleaning can be judged to have been reached. Actual plasma cleaning canbe conducted either during the processing of the required number ofwafers within cassette 1 a or 1 b, or before wafer processing control isadvanced to the next cassette following completion of processing of allwafers 20.

The sequence of plasma cleaning is described hereunder. This sequenceapplies when two dummy wafers 30 of all those (in this case, 25 wafers)stored within cassette 1 c are processed in etching chamber 11 a or 11c.

The first unused or reusable dummy wafer 30 within cassette 1 c ispicked by transport unit 13. Although any dummy wafer stored withincassette 1 c can be picked at this time, the position numbers and usagecounts of all dummy wafers within the cassette are already stored intomemory to ensure that the wafers are always taken out in order with thelowest-usage-count wafer first. After the first wafer has been picked,it is carried into loading lock chamber 6 a located at the opposite sideto that of cassette 1 a, via gate valve (isolated valve) 12 a bytransport unit 13 in the same way it transports wafer 20 for etching.Loading lock chamber 6 a, after closing gate valve 12 a, isvacuum-exhausted down to the required vacuum pressure by vacuum exhaustunit 3, then gate valve 12 b and gate valve (isolated valve) 15 a areopened, and dummy wafer 30 is carried from loading lock chamber 6 a toetching chamber 11 a via vacuum transport chamber 16 by transport unit14. Subsequently, dummy wafer 30 is placed on samples mount 8 a. Afterclosing gate valve 15 a, etching chamber 11 a with the dummy wafermounted inside provides plasma cleaning under the required conditions.

During this time, loading lock chamber 6 a closes gate valves 12 a and12 b and is then returned to the original atmospheric pressure by gasinduction unit 4. Next, loading lock chamber 6 a opens gate valve 12 aand carries dummy wafer 30 into loading lock chamber 5 a by transportunit 13 in the same way the first dummy wafer 20 was carried. Afterclosing gate valve 12 a, loading lock chamber 6 a is vacuum-exhausteddown to the required vacuum pressure by vacuum exhaust unit 3 again,then gate valve 12 b and gate valve (isolated valve) 15 b are opened,and the second dummy wafer 30 is carried from loading lock chamber 6 ato etching chamber 11 b via vacuum transport chamber 16 by transportunit 13. Subsequently, gate valve 15 b is closed and then the dummywafer is provided with plasma cleaning.

After plasma cleaning of etching chamber 11 a containing the first dummywafer 20 has been completed, gate valves 15 a and 12 c are opened. Useddummy wafer 30 is carried out from etching chamber 11 a into unloadinglock chamber 6 b by transport unit 14, and following this process, gatevalve 12 c is closed. Subsequently, unloading lock chamber 6 b isreturned to the original atmospheric pressure by gas induction unit 4and then gate valve 12 d is opened. Used dummy wafer 30 that has beencarried out into unloading lock chamber 6 b is taken out into theatmosphere via gate valve 12 d by transport unit 13 and then returned tothe original position within cassette 1 c.

After plasma cleaning of etching chamber 11 b, the second dummy wafer 20is likewise returned to the original position within cassette 1 c.

In this manner, used dummy wafers 30 are returned to the originalpositions within cassette 1 c and this cassette is always stocked withdummy wafers 30. After all dummy wafers 30 within cassette 1 c haveundergone plasma cleaning or have been reused several times to reach thescheduled usage count, all these dummy wafers 30 and cassette 1 c arereplaced together. The replacement timing of this cassette is controlledby control unit 19 and the appropriate instruction signal is sent to thehost control unit that controls the line transport robot, or to theoperator.

The above description of plasma cleaning applies to continuous plasmacleaning of etching chamber 11 a or 11 b using only any two of all dummywafers 30 stored within cassette 1 c. Other processing methods, however,can also be used.

For example, etching chambers 11 a or 11 b can likewise be provided withplasma cleaning sequentially using one dummy wafer 30. In this exampleof plasma cleaning, unprocessed wafer 20 in an etching chamber otherthan that which is to undergo plasma cleaning can be provided withetching and the apparatus can be cleaned without the etching processbeing interrupted.

In another example of a plasma cleaning method in which an etchingchamber, a post-processing chamber, a film-forming chamber, and othertypes of processing chambers are to be used and wafers are sequentiallysent to each such chamber for processing, dummy wafers 30 can also besent during sequential processing of wafers 20 stored within cassette 1a or 2 a, and these dummy wafers 30 are merely passed through aprocessing chamber not requiring plasma cleaning. In this case, dummywafers 30 are processed only after arriving at the processing chambersthat require plasma cleaning, whereby the corresponding processingchambers can be provided with plasma cleaning as appropriate.

According to these embodiments, a cassette containing dummy wafers and acassette containing the wafers to be processed can be arranged togetherin the atmosphere, then only dummy wafers are loaded from the cassetteinto the apparatus during the cleaning process by activating the sametransport unit as that used for carrying the wafers to be processed, andafter plasma cleaning, used dummy wafers can be returned to theiroriginal positions within the cassette. The adoption of this methodmakes it unnecessary to provide a special mechanism for plasma cleaningand thus enables the apparatus to be simplified. Also, plasma cleaningdoes not need to be handled as a special processing sequence, and thiscleaning process can be incorporated into normal etching to perform aseries of operations efficiently.

In addition, since plasma-cleaned dummy wafers are automaticallyreturned to their original positions within the cassette placed in theatmosphere, used dummy wafers are not placed in mixed form withunprocessed or processed wafers in the vacuum chamber. Unlikeconventional apparatuses, therefore, the apparatus based on the presentinvention does not cause wafer contamination with dirt or residualgases.

Furthermore, since used dummy wafers are not only automatically returnedto their original positions within the cassette, but also controlled interms of usage count, it is possible to avoid confusion between useddummy wafers, unused dummy wafers, dummy wafers low in usage count, anddummy wafers high in usage count, and thus to use each dummy waferefficiently and without inconvenience during plasma cleaning.

Furthermore, a plurality of processing chambers are provided, wafers andtheir dummies can be carried using the same transport unit, and thecontrol unit controls the cleaning timing of each processing chamber toenable timely plasma cleaning. These, in turn, enable arbitrary cleaningtime period setting, dry cleaning without interruption in the flow ofprocessing, and efficient processing for improved production efficiency.

In a configuration as described above, the axial line passing throughthe middle of the vacuum transport chamber and the locking unit is takenas line A; the axial line passing through the middle of the vacuumtransport chamber and that of etching chamber 11 a is taken as line B;and the axial line passing through the middle of the vacuum transportchamber and that of etching chamber 11 b is taken as line C.

Etching chambers 11 a and 11 b, which are vacuum processing chambers forprocessing wafers, are both formed by a UHF-ECR reactor. Two suchchambers are provided only at the opposite side to that of the lockingunit across vacuum transport chamber 16, symmetrically with respect toaxial line A passing through the middle of vacuum transport chamber 16and locking unit 6. Also, the foregoing two etching chambers, 11 a and11 b, are arranged at the acute angle, alpha, formed by lines B and C,and at the opposite side to that of vacuum transport chamber 16, andatmospheric loader 1, vacuum loader 7, and locking unit 6 are arrangedin T-shaped form.

As shown in FIG. 4, UHF-ECR antennas 110 a and 110 b are parallel to theabovementioned axial line A and are opened at the opposite side to thatof the vacuum transport chamber. The structure of the antennas isdescribed hereunder.

Prior to antennas 110 a and 110 b being opened, magnetic fieldgenerating units 101 a and 101 b used in etching chambers 11 a and 11 b,respectively, and antenna power lines 120 a and 120 b are lifted off bylifting unit 200. Other components of the antenna sections are detailedhereunder. Also, see FIG. 8.

The procedures for disassembling and reassembling the apparatus based onembodiments of the present invention, and the methods of removing thecomponents of the apparatus will be described hereunder with referenceto FIGS. 5 to 7.

FIG. 5 is a perspective view of the main section of the plasma etchingapparatus, with part thereof being shown in cross section in order torepresent the maintenance status based on the present invention. Abovethe side wall 102 mounted on vacuum chamber 105 there is installed anantenna 110, around which a magnetic field generating unit 101 isinstalled, and antenna power line 120 is connected to antenna 110 vialead-in terminal 126.

For apparatus disassembly during wet cleaning, processing chamber 100and vacuum chamber 105 are exposed to the atmosphere, and lead-interminal 126 that connects the antenna 110 to the antenna power line 120is disconnected.

The next step is shown in FIG. 6. First, as indicated by arrow (1) inFIG. 6, magnetic field generating unit 101 and antenna power line 120(not shown) are lifted by lifting unit 200 and then are fixed at aposition that facilitates maintenance. Next, as indicated by arrow (2),antenna 110 is opened by being rotated about the shaft of hinge 118until the antenna is disposed in an almost horizontal position, and thenplate 115 and ring 116 are lifted off as indicated by arrows (3) and(4). In this case, as shown in FIG. 4, antenna 110 is rotated and heldat the operator side, which is the opposite side to that of vacuumtransport chamber 16.

The next step is shown in FIG. 7. As indicated by arrows (5) and (6),side wall inner unit 103 and bottom cover 135 are lifted off.

Also, focus ring 132 of the bottom electrode is removed. Removedcomponents are subjected to processing, such as removal of filmdeposits, ultrasonic cleaning, and drying. Subsequently, all removedcomponents are reinstalled using the reverse procedure to that describedabove. Next, the apparatus is restored to the original status and thenundergoes vacuum evacuation.

Subsequently, the arrival of processing chamber 100 at the requiredvacuum pressure is confirmed, and then, as required, foreign substancechecks and rate checks are performed. After normal operation of theapparatus has been confirmed, it is restored to the intended operationalstatus and wet cleaning is completed. With one complete set of availablereplacement components at hand, since immediate restoration and vacuumevacuation of the apparatus is possible, its downtime (Good Wafer toGood Wafer) can be minimized.

Furthermore, improvement of wet cleaning efficiency by the adoption ofan appropriate measure, such as using no bolts in the sealed areas orconnections of the vacuum flange section, reduces apparatus downtime toabout three to four hours, thus maximizing apparatus availability.

In this embodiment, as shown in FIG. 6, since antenna. 110 can be openedby rotating it about the shaft of hinge 118, the entire antenna does notneed to be removed by lifting it from the processing chamber, nor areany burdens of lifting heavy objects imposed on maintenance personnel.Also, since antennas 110 a and 110 b are rotated and held in the samedirection, both antennas can be easily serviced and do not interferewith one another, with the result that their arrangement is smooth andeffective use of their spaces is possible. As already described, sinceplate 115 and ring 116 can also be easily removed just by lifting themin the directions of arrows (3) and (4), the maintenance efficiency canbe improved and the likelihood of components being damaged is reduced.

FIG. 8 is a top plan view of a full-flat open-structured vacuum vessel,as seen when it is mounted in a plasma processing system according toanother embodiment of the present invention. This system has two plasmaprocessing chambers, E1 and E2, and wafer samples are carried fromloader mechanism 151 through loading lock chamber 152 to buffer chamber153, and the samples are then transferred from sample transportmechanism 154 to plasma processing chambers E1 and E2.

In FIG. 8, the status of plasma processing chamber E1, as it appearswhen system assembly is completed, is shown, and magnetic fieldgenerating unit 101 and antenna power line 120 are mounted above vacuumchamber 105. Likewise, plasma processing chamber E2 during wet cleaningis shown, in which case, the inside of processing chamber 100 is exposedto the atmosphere and antenna 110 is opened by hinge 118 to take a fullyflat state. Magnetic field generating unit 101 and antenna power line120 are moved away to a position that facilitates maintenance.Maintenance personnel M present in the maintenance area can easilyperform maintenance operations because antenna 110 is opened in thedirection of the maintenance personnel M (namely, outward with respectto base frame 150 of the system) and is about half protruded withrespect to base frame 150. This antenna is not projected too far, nordoes it occupy a superfluous space in the maintenance area. It becomespossible, by mounting a plasma processing chamber (reactor) of full-flatopen structure in this way, to implement a plasma processing system wellbalanced between total configurational compactness and maintainability.

Although, in FIG. 8, magnetic field generating unit 101 is as shownprotruding from the system area, this unit actually does not protrudeoutward after it has been moved away in the upward direction of plasmaprocessing chamber E2.

Referring again to FIG. 1, in the foregoing configuration, two etchingchambers are provided only at the opposite side to that of the lockingunit across the vacuum transport chamber, symmetrically with respect tothe axial line passing through the middle of the vacuum transportchamber and the locking unit, and the foregoing two vacuum processingchambers are arranged at an acute angle, at the opposite side to that ofthe vacuum transport chamber, and in linear form along line D in allvacuum chambers of the vacuum processing apparatus. Line D is parallelto line E that connects the centers of the vacuum transport chambers.Under such arrangement of the vacuum processing apparatus components,since the antennas are opened in a vertical direction relative to linesD and E, even when the adjacent vacuum processing chambers of the vacuumprocessing apparatus are exposed to the atmosphere at the same time, asufficient maintenance space is ensured, compared with the case in whichthe antennas are opened in the direction from the vacuum transportchamber toward the vacuum processing chambers.

According to the present invention, it is possible to minimize increasesin manufacturing costs, while at the same time providing flexibility toincreases in sample size, and to provide a vacuum processing apparatusthat has excellent maintainability. Also, incorporation of such vacuumprocessing apparatus into semiconductor manufacturing equipment makes itpossible to ensure the complement of vacuum processing apparatus andminimize manufacturing costs while at the same time providingflexibility to increases in sample size, and to supply semiconductormanufacturing equipment whose maintainability does not deteriorate.

Furthermore, according to the present invention, one portion of thevacuum vessel constituting the processing chambers can be constructed asa section that can be opened and closed, and when this section directsthe processing chambers upward, components can be maintained in theirphysically stable status at the operator side in an almost horizontalposition by friction or by a securing section. Accordingly, since thetop of the processing chambers opens in the direction of the maintenancearea, maintenance personnel can easily both access the processingchambers and perform maintenance operations from the top. As a result,the maintenance personnel can easily handle components duringmaintenance and maintainability is improved, which in turn enables therealization of a plasma processing apparatus which has excellentmaintainability, is easy to use and contributes to an improvement inproductivity.

What is claimed is:
 1. Vacuum processing apparatus comprising: aplurality of cassette tables arranged close to each other, anatmospheric transport unit for carrying wafers from or to said cassettetables, a plurality of vacuum processing chambers, a vacuum transportchamber communicated with said vacuum processing chambers, and loadingand unloading lock chambers equipped with gate valves for connectingsaid atmospheric transport unit and said vacuum transport chamber;wherein each of said vacuum processing chambers has side wall innerunits and antennas so mounted as to permit disassembly, and saidplurality of vacuum processing chambers are arranged symmetrically withrespect to an axial line passing through the middle of the vacuumtransport chamber and lock chambers, only at the opposite side of thelock chamber across the vacuum transport chamber, and in such a mannerthat the vacuum processing chambers form an acute angle with respect tothe vacuum transport chamber, wherein said antennas are directed almostin parallel to said axial line, and each of said antenna is opened inalmost horizontal position at the opposite side of said vacuum transportchamber.